The present invention relates generally to manufacturing processes, and, more specifically, to laser forming.
Industrial lasers are continually being developed for various manufacturing processes. Lasers are currently being utilized for welding, cutting, and drilling operations in various materials, including metal and high strength superalloys which have enhanced strength at high temperature as typically found in modern gas turbine engines.
Laser forming is yet another process being developed for industrial applications in which the laser beam is used to precisely heat and deform a metal substrate for changing its shape. The localized heating by laser will typically not exceed the melting temperature of the parent material but must be sufficiently hot to effect local thermal deformation. At such elevated temperatures, the parent material may be subject to changes in the microstructure thereof, as well as surface oxidation and surface discoloration or associated marks.
However, these adverse affects may be reduced or eliminated by precisely controlling heating of the material during laser scanning thereof, and conducting such laser processing in a vacuum. Vacuum processing correspondingly requires a suitably large chamber for containing the workpiece and laser equipment which have associated complexity, cost, and increased process time required for evacuation of the ambient air.
Instead of evacuating the vacuum chamber, an inert gas may be provided therein for protecting the workpiece material during heat generating processes such as welding or laser forming for example. However, the chamber must be sized to contain not only the workpiece but the associated welding or laser processing equipment.
Alternatively, the inert gas may be provided through gas nozzles to locally bathe the work site with the inert gas, and is therefore subject to the ability to suitably supply and maintain the inert gas over the workpiece while it remains at elevated temperature.
Accordingly, it is desired to provide an improved laser forming apparatus in which the workpiece is locally protected by an inert gas throughout the laser scanning process.